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Thread: Stupid inequalities!

  1. Nov 24th, 2002, 08:01 PM #1
    SilverSprite
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    Stupid inequalities!

    Could someone lend a hand in solving (x+3)(x-2)>=0 algebraically. Thanks for any help!
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  2. Nov 25th, 2002, 02:01 AM #2
    sql_lall
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    Talking Sure

    Ok, not really the most algebraic, but here goes:
    interecepts: x = -3 and x = 2
    graph concave (x^2 coefficient positive)
    => (x+3)(x-2)>=0 when x <= -3 or x >= 2
    sql_lall
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  3. Nov 25th, 2002, 04:25 PM #3
    SilverSprite
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    No i knew how to do that. I call that graphically. If anyone could help me algebraically? Thanx anyways sql_lall.
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  4. Nov 25th, 2002, 06:30 PM #4
    bugzpodder
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    (x+3)(x-2)>=0

    [(x+3)>=0 Intersection (x-2)>=0] U (union) [(x+3)<=0 Intersection (x-2)<=0]

    you can take it from here
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  6. Nov 26th, 2002, 05:25 PM #5
    Kalkewl8ter
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    If two numbers multiply to a non-negative number, they cannot have opposite signs. x+3>x-2 ALWAYS, from which follows:

    x-2>=0 or x+3<=0
    x>=2 or x<=-3
    Merry Math Making!
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